(1) Field of Invention
The subject invention relates to an improved blow tube for use with a core-forming blow plate of the type utilized for making foundry cores of sand. The sand is blown under pressure through a material-dispensing passage in a blow plate assembly and through a blow tube into a cavity in a core box. The sand cores formed in the core box are utilized in the casting of metal in foundries. Such cores take various different configurations and sizes. Consequently, the cavities which form the cores are of different volumes and configurations which in turn requires various different configurations of blow tubes in terms of diameter, length and outlet or discharge opening into the core box. Therefore, it has been necessary to stock various different blow tubes having different configurations to satisfy different core making situations.
(2) Description of the Prior Art
Typically, the prior art blow tubes are fabricated from metal sleeves, which sometimes include cooling chambers, or are fabricated of a plastic material; however, the prior art blow tubes when finished and ready for use are of a fixed length and are specially configured at one end for attachment to the blow plate assembly.